1. Field of the Invention
The apparatus of the present invention relates to torque tools. More particularly, the present invention relates to a uniquely designed hydraulic torque wrench for tightening and loosening a compressor jam nut of the type for securing a compressor shaft which would prevent access to the jam nut with a closed end wrench.
2. General Background of the Invention
Throughout industry, compressors are used for supplying air or other fluid under pressure to operate industrial machinery. The type of compressor particular to this invention is the type which is driven by an engine, such as an internal combustion engine. The engine operates the compressor through the use of a compressor shaft extending from the engine to the compressor for driving the compressor. In such an arrangement, the compressor shaft is secured in place with the use of a threaded member referred to as a compressor jam nut. The jam nut, well known in industrial applications, has the compressor shaft running through it, so that the nut may be torqued up to a certain foot pounds to secure the nut in place.
One of the problems confronted in this arrangement, the fact the compressor shaft is connected on both ends, one end to the engine, and the second end to the compressor, so that access to the nut, in order to torque it to the desired torque, is severely limited. For example, because the nut is not easily accessible, and because the shaft running through it precludes the nut from accommodating a "ratchet" type wrench, an opened wrench, commonly known as a crescent wrench, must be utilized. However, the necessary amount of torque, which at times may be at least 14,000 ft.-lbs., cannot be applied through the strength of a person. Therefore, when an open-ended wrench is used, in the present state of the art, requires that one person hold the wrench in place upon the jam nut, and a second man strike the wrench handle with a sledge hammer a certain number of times. At the present, it is suggested, that to reach a torque of approximately 14,000 ft.-lbs., the wrench must be struck 78 times with a 16-lb. sledge hammer. One can readily see this method of torquing up a jam nut as being quite archaic, if not approaching barbaric in its application.
One possible solution to the problem of supplying sufficient torque would be through the use of a hydraulic torque wrench, for example of the type as seen in U.S. Pat. No. 5,097,730, incorporated hereinto by reference. In the use of torque wrenches, most torque wrenches are closed in the sense that the wrench's working end fits over the head of a bolt or a nut for access to the multi-sided piece in order to loosen it or tighten it. However, as stated earlier, a compressor jam nut is positioned along the body of a compressor shaft which is secured on both its ends, and has to be loosened or tightened. However, since a regular torque wrench is closed end, a conventional torque wrench, as is currently known in the art, cannot slip over the jam nut because of the compressor shaft running through it. Therefore, there is a need in the industry for a new type of a wrench which can be opened and would allow the tool to be placed around the nut for loosening or tightening the nut which the nut is secured to the compressor shaft.